The present invention relates to an electrophotographic copying machine and, more particularly, to a circuit for quickly initializing and stabilizing the property of a photoreceptor in an electrophotographic copying machine.
An electrophotographic copying machine produces an electrostatic latent image onto a photoreceptor corresponding to a pattern image on a document such as a manuscript or book to be copied. Toner particles are electrostatically adhered to the latent image, so that the latent image becomes visible as a toner image. The toner image on the photoreceptor is transferred onto a copy paper via a transference charger.
Conventionally, around the photoreceptor, various means are provided for causing the various processes including charging, light exposure, developing, transferring, charge removing and cleaning. In addition, a copy paper feeding means is provided for feeding the copy paper into the transferring means and there is a fixing device.
After a full operation of copying the first document, all the various means are stopped in view of the life times of the photoreceptor and the mechanical elements, so that they are placed in the copy ready. In response to the next copy instruction, all the means are started to be activated to copy the second document.
To stabilize the property of the photoreceptor, before starting a new copy operation, the receptor is fully revolved without any copying operation in a condition identical with the copying operation condition while all the means are activated. At this time, no copy paper is fed and transferred. This is called a "pre-copy process or operation" herein. The first copy operation is carried out after the pre-copy process. This results in prolonging the copying time because the time for the pre-copy process is added to the net copy operation time. When a plurality of documents are intended to be copied, such pre-copy processes are repeated each time a new document replaces the old one. This prolongs the copying time.